Re: pci passthrough issue introduced between 4.14.1 and 4.15.0

[AL13N <alien@xxxxxxxx>]

AL13N schreef op 2021-06-01 16:48:
> AL13N schreef op 2021-06-01 16:44:
> > Jan Beulich schreef op 2021-06-01 16:33:
> > > On 01.06.2021 16:06, AL13N wrote:
> > > > Jan Beulich schreef op 2021-06-01 12:08:
> > > > > On 01.06.2021 09:36, AL13N wrote:
> > > > > > Not 100% it's a bug or something i did wrong, but,
> > > > > >
> > > > > > with xl create i start a PV with 3 pci passthroughs
> > > > > >
> > > > > > after wards, xl pci-list shows all 3 nicely
> > > > > >
> > > > > > looking at the domU boot logs, pcifront is only creating one pci
> > > > > > device
> > > > > > and lspci in the guest shows only 1 pci entry
> > > > > >
> > > > > > in at least 4.14.1 it still works.
> > > > > This reminds me of my report at
> > > > > https://lists.xen.org/archives/html/xen-devel/2021-03/msg00956.html
> > > > >
> > > > > Meanwhile the proposed pciback change has gone in upstream:
> > > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/xen/xen-pciback?id=c81d3d24602540f65256f98831d0a25599ea6b87
> > > > >
> > > > > I wasn't, however, aware that this may have been an issue going
> > > > > from 4.14.1 to 4.15.0, i.e. something that was presumably (as
> > > > > George also has just said) a regression in the tools. Or else I
> > > > > probably wouldn't have suggested taking care of this in Linux.
> > > > > Nevertheless you may want to give that change a try.
> > > > Well, both tests have only different tools en hypervisor, no kernel 
> > > > was
> > > > changed between both tests, neither in dom0 or domU , so, it might 
> > > > not
> > > > be pciback?
> > > Well, if the problem was introduced in the tools and this having been
> > > the reason for me running into the same or a similar issue, the patch
> > > may still address the issue, even if - in case it's a regression in
> > > the tools - it would have been better to also address the issue 
> > > there.
> > > As said, when analyzing the issue I didn't have indications of 
> > > changed
> > > tool stack behavior, i.e. I assumed the problem would have always 
> > > been
> > > there.
> > Yeah after rereading the thread, i got this impression.
> >
> > though after looking at a quick grep:
> >
> > [alien@localhost xen]$ git log RELEASE-4.14.1..RELEASE-4.15.0
> > --oneline --decorate -- tools/xl/ | grep -i pci
> > bdc0799fe2 libxlu: introduce xlu_pci_parse_spec_string()
> > 96ed6ff297 libxlu: introduce xlu_pci_parse_spec_string()
> > 929f231140 libxl: introduce 'libxl_pci_bdf' in the idl...
> > c00da82355 libxl: add libxl_device_pci_assignable_list_free()...
> > 7499b22ba1 libxl: make sure callers of libxl_device_pci_list() free
> > the list after use
> > 6c2590967f xl: s/pcidev/pci where possible
> >
> >
> > it doesn't seem like one of these? (well, i've not familiar with any
> > of the xen code)
> >
> > This mailing list is the correct place for the toolstack too? right?
> i forgot the libs....
>
> [alien@localhost xen]$ git log RELEASE-4.14.1..RELEASE-4.15.0
> --oneline --decorate -- tools/libs/light/ | grep -i pci
> 9cd5bbf536 libxl / libxlu: support 'xl pci-attach/detach' by name
> 57bff091f4 libxl: add 'name' field to 'libxl_device_pci' in the IDL...
> d473d74af3 libxl: stop setting 'vdevfn' in pci_struct_fill()
> 8bf0fab142 libxl / libxlu: support 'xl pci-attach/detach' by name
> 5ab684cb3e libxl: introduce
> libxl_pci_bdf_assignable_add/remove/list/list_free(), ...
> 66c2fbc6e8 libxl: convert internal functions in libxl_pci.c...
> 929f231140 libxl: introduce 'libxl_pci_bdf' in the idl...
> 413fd4e4e9 libxl: use COMPARE_PCI() macro is_pci_in_array()...
> c00da82355 libxl: add libxl_device_pci_assignable_list_free()...
> 7499b22ba1 libxl: make sure callers of libxl_device_pci_list() free
> the list after use
> f8cfb85719 libxl: remove get_all_assigned_devices() from libxl_pci.c
> 4951b9ea80 libxl: remove unnecessary check from libxl__device_pci_add()
> fe91a3aadc libxl: generalise 'driver_path' xenstore access functions
> in libxl_pci.c
> b5429d65e1 libxl: stop using aodev->device_config in 
> libxl__device_pci_add()...
> a825ab3a6b libxl: remove extraneous arguments to do_pci_remove() in 
> libxl_pci.c
> 33e1c5a5a8 libxl: s/detatched/detached in libxl_pci.c
> d8cba539f2 libxl: add/recover 'rdm_policy' to/from PCI backend in 
> xenstore
> 0fdb48ffe7 libxl: Make sure devices added by pci-attach are reflected
> in the config
> fce69998ed libxl: make libxl__device_list() work correctly for
> LIBXL__DEVICE_KIND_PCI...
> e43780f15f libxl: s/pcidev/pci and remove DEFINE_DEVICE_TYPE_STRUCT_X
>
>
> what is this "f8cfb85719 libxl: remove get_all_assigned_devices() from
> libxl_pci.c" doesn't it seems sus?
or maybe "7499b22ba1 libxl: make sure callers of libxl_device_pci_list() 
free the list after use" , if between adding pci, it also does the list 
and then maybe it gets freed and thus stops after the first one?
sounds like a longshot, tbh...

anyone have an idea which it might be? or should i look in other places?